Oil-injecting apparatus for asphalt mixers



Dec. 18, 1928. 1,695,722

. w. A. SMITH OIL INJECTING- APPARATUS FOR ASPHALT MIXERS Fiied Nov. 29, 192'! Imienmr j%/far Patented Dec. 18,1928. 1

A 1,695,722- UNITED s'm'rns PATENT OFFICE,

WALTER 1. SMITH O]? HOUSTON, TEXAS.

om-mmo'rino APPARATUS Foa serum nixnas.

Application filed November 29, 1827. Serial No. 236,435.

The present invention relates to concrete mixers generally and more particularly to the oil injecting apparatus used therew th:

The apparatus commonly used for injecting oil in an asphalt mixer comprises an oil line under pressure leading to the mixer and terminating interiorly of the drum thereof, said inner end having connected therto a nozzle. In the oil line there is disposed a valve remote from the nozzle since the nozzle is inaccessiblefor practical )urposes when the mixer is in use. It has een found that when the remotely located valve is turned ofi the 'oil in the line between the valve and the nozzle leaks out causing the formation of bubbles in the line which when the valve is again turned on fbr the next operationcauses what are known'in the art as oil balls and these weaken the asphalt particularly pavement and the like.-

The prime object of the present invention is to provide an apparatus which enables the oil line to be cut oil immediately at the nozzle in an automatic manner when the remotely-located valve is turned off.

With the above and numerous other objects in view, as will appear as the description proceeds, the invention resides in certain novel features of construction, and in the combination and arrangement of parts as will be hereinafter more fully describedleads from the tank 5 to the pump 6 and.

from the pump 6 past the batch tank" 7, being connected to said batch tank by branch pipes 9 and 10. Valves 11 and 12 are mounted in the line 8 at the juncture of branch pipes 9 and 10 therewith respectively; The numeral 14 denotes an asphalt mixer drum into which the pipe line 8 leads coax'ially therewith in the usual well known manner. Letter V- denotes my improved valve which functions as a coupler between the line 8 and a-nozzlo 15 into the drum .14.

With the exoeption of the valve the paratus is identical with that now commonly inuse, the Valve V being-the added element to the"combination involving the es sence of the present invention. Th valve V is illustrated to advantage in Figures 2 and 3 of the drawings comprlsing an elongated casing the intermediate portion of which is reduced as at 16 and the end portions diametrically enlarged as at 17 and 18. The reduced intermediate portion 16 causes the formation of shoulders 19 -and 20. The

shoulder 19 is beveled to form a valve seat against which is closable a valve element 21 mounted on a cruciform guide structure 22 ref longitudinally movable in the reduced por- I tion 16 and terminating'in a shank 23 dis posed in the large end 18, :A conical coil spring 24 is disposed about the shank 23 and its larger 'end' impinges against the shoulder 20 and its smaller end impinges against, a nut 25- threaded on the shank 23. Obviously the spring 24 maintains the valve 21 closed and this yalve is"openable in one direction only, that is toward the nozzle 15 since the end 17 threadedly receives the nozzle while the end 18 threadedly receives the inner terminal of the pipe line 8.

' With the use of this valve -V it will be .seen that when the valve 12 is turned on so that oil under pressure flows through the Y pipe line 8 to the nozzle 15 the oil overcomes the tension of the spring 24' opening the valve 21 and closes its nozzle 15 and as soon as the valve 12 is closed the pressure ceases and therefore the valve element 21 will close against the seat 19 through the action of the spring 24 thus preventing any of the oil trapped between the valve 12 and the valve V from flowing into the nozzle 15' and thereby preventing the;formation of the undesirable oil balls mentioned above.

It is thought that the construction, utility,

operation and advantages of this invention will now be quite apparent to those skilled in this art without a more detailed description thereof. The present embodiment of the invention has been disclosed in detail merel by way of'example since'in actual practice-it attains the features of advantage enumerated. as desirable in the statement of the invention and the above description. It

will be apparent that changes in the details of construction and-in the combination-and arrangement of parts -may be resorted to without departing from the spirit or scope I of the invention as-hereinafter claimed on cl 'uciform l nember connected theieto' slidable longitudinally in the reduced persacrificing any of; its advantages.

- including an elongated tubular casing hav- Having thus described myinvention, what f tion of-the bore and terminating in a shank, I claimfas new; is: Y a v a.

A valve structure of the class described thexother shoulder ind means on th shank which the spring impinges or noring its bore reduced intermediate its ends to finally holding the valve element closed.

provideap'air of-spaced shoulders, one of the In testimony whereof I afiix my signashoulders forming a valve seat, a valve eletum.

ment closable against the seat and having a WALTER A. SMITH.

. spring disposed about the shank abutting 

